Feasibility Phase
Total Page:16
File Type:pdf, Size:1020Kb
Network Analysis Celtic Interconnector Feasibility Study November 2016 The sole responsibility of this publication lies with the author. The European Union is not responsible for any use that may be made of the information contained therein. Table of Contents Executive Summary ................................................................................................................... 1 1. Introduction ......................................................................................................................... 2 2. Identification of Feasible Connection Points ........................................................................ 2 3. Analysis Methodology and Assumptions ............................................................................. 3 4. Analysis Results: Connection at Knockraha ........................................................................ 5 5. Analysis Results: Connection at Great Island ...................................................................... 6 6. Comparison of Connection Points ....................................................................................... 8 7. Conclusion .......................................................................................................................... 8 Appendix A ................................................................................................................................ 9 Table of Figures Figure 1 Map of Irish transmission network showing potential connection points for Celtic Interconnector ............................................................................................................................ 3 Figure 2 Map of Irish transmission network showing locations of existing HVDC interconnectors .................................................................................................................................................. 5 Figure 3 Areas of the network with network violations for connection at Knockraha ................... 6 Figure 4 Areas of the network with network violations for connection at Great Island ................. 7 Network Analysis – Celtic Interconnector Feasibility Study Page i Executive Summary This analysis was requested as part of the investigations into the feasibility of building an interconnector between Ireland and France, known as the Celtic Interconnector. The purpose of this analysis is to assess the potential impact of the Celtic Interconnector on the transmission system when it is connected at different connection points and to do a relative comparison of these impacts. Due to the significant capacity of the interconnector at 700 megawatts (MW), it must connect to an existing substation on either the 220 kV or 400 kV network. Based on their geographic location along the south coast of Ireland and their connectivity within the transmission system, the two strongest potential connection points for the Celtic Interconnector are the substations at Knockraha in County Cork and Great Island in County Wexford. The analysis undertaken clearly indicates that the transmission system can accommodate the potential power flows from the Celtic Interconnector significantly better with the connection point at Knockraha rather than a connection point at Great Island. Connection at Great Island would likely require significant levels of upgrading of existing transmission system infrastructure and/or new infrastructure in comparison with the Knockraha option. Network Analysis – Celtic Interconnector Feasibility Study Page 1 1. Introduction EirGrid is undertaking investigations into the feasibility of constructing a high voltage direct current (HVDC) interconnector between Ireland and France, known as the Celtic interconnector. If the project proceeds, it would connect a substation in France with a substation in Ireland, using a subsea cable. The analysis detailed in this report was requested as part of these feasibility investigations. The purpose of this high level technical analysis is to assess the potential impact of the Celtic Interconnector on the transmission system when it is connected at different connection points and to do a relative comparison of these impacts. This analysis will form one part of the decision making process used to identify a connection point onto the existing transmission network for the Celtic Interconnector. 2. Identification of Feasible Connection Points Due to the significant capacity of the interconnector (700 MW) it must connect to an existing substation on either the 220 kV or 400 kV network. Due to the geographic location of France in relation to Ireland, a connection point in the south or south east of Ireland is the most suitable. The substations at Knockraha in County Cork and Great Island in County Wexford have been identified as the two strongest potential connections points for the Celtic Interconnector. These have been identified based on their location along the south coast of Ireland and their connectivity within the transmission system. These connection points are illustrated in Figure 1 which comprises a map of the transmission network. Knockraha 220 kV substation is located to the north east of Cork city. It is well connected to the rest of the 220 kV network via six 220 kV circuits and to the 110 kV network via six 110 kV circuits. It is close to a major hub of conventional generation totalling approximately 1,400 MW of generating capacity. It is also close to an area of high wind generation in the south west which will total approximately 1,900 MW once all contracted wind generation has connected. Great Island 220 kV substation is located in County Wexford. It is connected to the rest of the 220 kV network via three 220 kV circuits and to the 110 kV network via four 110 kV circuits. There is a 470 MW combined cycle gas turbine (CCGT) generator connected to the substation. Connection of the Celtic Interconnector at other well connected 220kV or 400kV substations that are more northerly, e.g. the existing Tarbert, Moneypoint, Killonan, Dunstown or Carrickmines substations, would significantly increase the length and therefore the cost of the interconnector and would make the interconnector not economically viable. Network Analysis – Celtic Interconnector Feasibility Study Page 2 SORNE HILL LOGUESTOWN TRILLICK CAM COLERAINE ARDNAGAPPARY COOLKEERAGH SPRINGTOWN LIMAVADY GARVAGH KILTOY LISAGHMORE RASHARKIN KILLYMALLAGHT LETTERKENNY BROCKAGHBOY SLIEVE KIRK MEENTYCAT BALLYLUMFORD MOYLE DRUMKEEN LARNE INTERCONNECTOR BALLYMENA KELLS WIND TIEVEBRACK STRABANE CAES KELLS CREAGH CRONCARKFREE ANTRIM KILROOT MAGHERAFELT NEWTOWNSTEWART GOLAGH BINBANE CLOGHER RATHGAEL MAGHERAKEEL Northern HANNAHSTOWN MULREAVY TREMOGE CURRAGHMULKIN Ireland NEWTOWNARDS OMAGH CASTLEREAGH DUNGANNON CATHALEEN'S OMAGH TAMNAMORE LISBURN FALL CLIFF SOUTH GORT TURLEENAN DRUMNAKELLY WARINGSTOWN BALLYNAHINCH ARMAGH TANDRAGEE BANBRIDGE ENNISKILLEN LISDRUM SLIGO TAWNAGHMORE CORDERRY NEWRY SRANANAGH AGHYOULE CORRACLASSY GORTAWEE CUNGHILL BELLACORICK NORTH MAYO GARVAGH MOY GORTAWEE OWENINNEY GLENREE ARIGNA DUNDALK SHANKILL RATRUSSAN LOUTH CARRICK MULLAGHARLIN -ON - SHANNON MEATH TONROE GILRA HILL CASTLEBAR ORIEL ARVA ORIEL OFFSHORE FLAGFORD WIND CARROWBEG CASTLETOWNMOOR DRYBRIDGE SLIABH BAWN NAVAN DALTON RICHMOND GORMAN LANESBORO PLATIN KNOCKUMBER STEVENSTOWN EAST-WEST INTERCONNECTOR BALTRASNA MULLINGAR WOODLAND GLASMORE PORTAN CLOON CORDUFF KINNEGAD HUNTSTOWN ATHLONE BELCAMP KNOCKRANNY CUILLEEN FINGLAS NORTH WALL SCREEB DERRYIRON DUNFIRTH POOLBEG SHELLYBANKS UGGOOL MAYNOOTH RINAWADE INCHICORE IRISHTOWN CASHLA THORNSBERRY BLAKE WEST DUBLIN CUSHALING SHANNONBRIDGE SALTHILL GALWAY CHERRYWOOD MOUNTLUCAS MONREAD CARRICKMINES SOMERSET KILTEEL FASSAROE NEWBRIDGE BARODA TYNAGH BRACKLONE DUNSTOWN KILINAPARSON POLLAPHUCA DERRYBRIEN OLDSTREET DALLOW TURLOUGH KNOCKAVANNA HILL PORTLAOISE ATHY BALLYBEG AGANNYGAL STRATFORD LAOIS IKERRIN NENAGH SHELTON ABBEY ARKLOW ENNIS CARLOW BOOLTIAGH BALLYRAGGET KELLIS LISHEEN DRUMLINE TULLABRACK ARDNACRUSHA BUNKIMALTA CUREENY THURLES SINGLAND LIMERICK PROSPECT MUNGRET BANOGE SEALROCK AHANE MONEYPOINT MONETEEN KILKENNY NORE CASTLEDOCKRILL LODGEWOOD TARBERT CASTLEFARM AUGHINISH KILLONAN CRORY KILPADDOGE CAUTEEN BALLYWATER CRANE CAHERNAGH RATHKEALE KILL HILL TIPPERARY KNOCKMULLEN KNOCKANURE TRIEN DROMADA ATHEA DOON BALLYDINE SUIR WEXFORD CAHIR CLAHANE ANNER CHARLEVILLE CLOGHBOOLA TRALEE GREAT ISLAND REAMORE KNOCKACUMMER WATERFORD CULLENAGH CORDAL GLENTANEMACELLIGOT KILLOTERAN BUTLERSTOWN GLENLARA OUGHTRAGH BALLYNAHULLA MALLOW BARRYMORE KNOCKEARAGH DUNGARVAN WOODHOUSE GARROW BALLYVOUSKILL BOGGERAGH CLONKEEN CLASHAVOON KNOCKRAHA COOMAGEARLAHY KILBARRY INNISCARRA GLANLEE MACROOM MARINA TRABEG Great Island HARTNETT’S COOMATAGGART COOLROE AGHADA CROSS CARRIGADROHID RAFFEEN GLANAGOW BARANADIVANE BRINNY BANDON BALLYLICKEY DUNMANWAY Knockraha Figure 1 - Map of Irish transmission network showing potential connection points for Celtic Interconnector 3. Analysis Methodology and Assumptions Methodology Power flow studies have been carried out to determine the potential network issues arising on the transmission system by the introduction of the Celtic Interconnector at each of the two connection points. From the network issues identified, a high level assessment of the potential level of transmission network reinforcement required to mitigate these issues has been undertaken for each connection point. Network Analysis – Celtic Interconnector Feasibility Study Page 3 It should be noted that a detailed analysis of the resultant potential